The percentage % of modulation is an indicator of the extent to which it is modulated.

Here is a picture of an unmodulated sine wave.

By comparison here is a picture of an Amplitude Modulated sine wave.

## Formula

The percent modulation is given by

*% _{M} = ((V_{MAX}-V_{MIN})/(V_{MAX}+V_{MIN})) * 100*

## Calculator

**Example**

In the following example, **V _{MAX}** = 2.5,

**V**= -0.5. Using these numbers in the calculator gives 150% modulation. This is an example of an overmodulated signal.

_{MIN}If **V _{MAX}** =

**V**, the sine wave is not modulated and the percentage modulation is 0.

_{MIN}